Question: The arithmetic sequence $(a_i)$ is defined by the formula: $a_i = 9 + 6(i - 1)$ What is $a_{14}$, the fourteenth term in the sequence?
Answer: From the given formula, we can see that the first term of the sequence is $9$ and the common difference is $6$ To find $a_{14}$ , we can simply substitute $i = 14$ into the given formula. Therefore, the fourteenth term is equal to $a_{14} = 9 + 6 (14 - 1) = 87$.